Hi Al,

Even with your .config the HEAD of acpi-topic-mustang does not boot with acpi=force.
Here are the messages appear on the console:

EFI stub: Booting Linux Kernel...
EFI stub: Using DTB from configuration table
EFI stub: Exiting boot services and installing virtual address map...
XhcClearBiosOwnership: called to clear BIOS ownership
XhcClearBiosOwnership: called to clear BIOS ownership
L3c Cache: 8MB

On 8/18/15 6:58 AM, Itaru Kitayama wrote:

Hi Al,

>Where does it "stall"? What's the last message you see? And if you're not
>using earlycon, please do so; that will help determine how far the boot is
>getting.

If I boot it with acpi=force, no output. Does my usage below look correct?

GRUB_CMDLINE_LINUX="earlycon=uart8250,mmio32,0x1c021000 acpi=force console=ttyS0,115200 loglevel=7"

>How were those checked?

In setup_arch() I was calling disable_acpi() right after the acpi_boot_table_init() call
as that makes the system get to the prompt.

I am about to build the kernel with your .config and test it on one of Mustangs
in the Linaro Austin lab. The Boot firmware version is 1.1.0-rh-0.15.

Itaru